Scientific paper ID 1884 : 2019/3
STUDY ON THE PROBABILITY OF A DANGEROUS FAILURE IN SAFETY CRITICAL SYSTEMS OF THE TYPE 2V2
Hristo Hristov, Mariya Hristova
The concept of a dangerous failure in the safety critical system is defined. A task is set to analyze the probability of a dangerous failure within a widely popular class of safety critical systems known as structures.
In the context of system failures, a comparison is made between computer processing and telecommunication transmission of messages. It is known that impulse errors of the individual discharges are (assumed as) independent and the code distance D between the functional vectors is a means of efficient protection against interference during the linear transmission of information. With the increase in distance D the probability qD to transition to a wrong vector abruptly decreases. In computer processing, this security method does not work. Any failure in a microprocessor device, irrespective of its nature (hardware or software), may generate with equal probability all erroneous output vectors N = 2v, where n is the number of vector discharges. The study is performed with the assumption of this condition. Two groups of failures influence system security: Common-Mode Failure (CMF) and Accidental Non-Identification (ANI). This paper is a part of a more extensive research that covers both groups, and yet it focuses on the second type of causes – accidentally non-identified failures ANI. Formulas are elaborated for assessment of ANI dangerous failures and their probability depending on the length of the vectors.
критични по безопасност системи поведение на системите след отказ надеждност безопасност опасни откази.Safety Critical Systems system behaviour after failure reliability safety dangerous failures.Hristo Hristov Mariya Hristova
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